We were setting the user status to offline without
checking for connections on other nodes in a cluster.
Now we implement a request-response mechanism for the whole
cluster and we check that before setting a user to offline.
https://mattermost.atlassian.net/browse/MM-57153
```release-note
Fix a bug where the user status would incorrectly be set to offline
without checking for connections in other nodes in an HA cluster.
```
Co-authored-by: Ibrahim Serdar Acikgoz <serdaracikgoz86@gmail.com>
Co-authored-by: Mattermost Build <build@mattermost.com>
Co-authored-by: Ben Schumacher <ben.schumacher@mattermost.com>